EDMONTON - A waste-water pipe at Suncor’s oilsands plant leaked into a pond of treated water Monday, and the resulting diluted water flowed into the Athabasca River, a company official said Tuesday.

Suncor spokeswoman Sneh Seetal said a pipe froze and burst, causing a leak that was discovered by an operator during rounds, which happens each shift. The pipe was 10 centimetres in diameter.

It is not known how much waste water flowed into the pond, which contained water that had already been treated and was ready to be returned to the river.

Communities downstream from the plant were notified about the incident and tests are underway to determine if the river water has been affected. Tests results will be available in the coming days.

Both the company and government officials emphasized they are taking the incident seriously.

“We have determined that some process-affected water went into that partially frozen outfall pond and then to an approved discharge point, where it was then diluted with water that is approved for and intended for release,” Seetal said. “From there it would have flowed into the river.”

“An approved discharge point is an area approved by regulators for water to flow into the river,” Seetal said.

“Process-affected water” is water used in Suncor’s extraction and upgrading process that has not yet been treated, Seetal said.

Environment Minister Diana McQueen was not available to comment Tuesday, but press secretary Wayne Wood said the government is taking the incident “very, very seriously.

“What happened at Suncor is a good example that our system does work, that our crews are able to respond very quickly to these kinds of situations and make sure that industry is meeting its obligations,” Wood said.

“We are being very diligent in making sure that we’re open and transparent about this particular incident, and when we have the results of the water sampling delivered to us we’ll make sure that Albertans know what those results are, in particular those Albertans who are in the immediate area.”

Seetal said the leak was reported to the province about 1 p.m. Monday, but Alberta Environment spokeswoman Jessica Potter said the province learned of the incident at 1:45 p.m.

Potter said the Alberta Environment Support and Emergency Response Team (ASERT) was immediately dispatched to the site and the flow was reduced to a trickle by 2:30 p.m. The leak was fixed by 4 p.m.

The ASERT team handed the file to a regional compliance officer Monday evening. The compliance officer will review the incident and can recommend charges under Alberta’s Environmental Protection and Enhancement Act, if he or she determines they are warranted.

Chief Allan Adam of the Athabasca Chipewyan First Nation expressed concerns about protection of the environment in northern Alberta.

“As chief of a downstream community in the region, this type of incident is of great concern and substantiates my community’s longtime concerns of the negative and adverse impacts this industry has on our ecosystem, traditional lands and cultural rights,” Adam said in a statement.

Jennifer Grant, oilsands director at the Pembina Institute, urged the province and the company to be fully transparent about what happened and the investigation that ensued.

“This is another example of the fact that there is no energy project without risk,” Grant said. “The environmental risks of developing the oilsands needs to be backstopped by rigorous oversight and enforcement.”

Greenpeace Canada spokesman Mike Hudema said Albertans should not have to worry whether their drinking water is safe.

“Many of the chemicals in tar sands operations are known carcinogens and extremely toxic,” Hudema said. “It’s time the government stepped in and stopped these companies from operating until they can prove they can do it without impacting communities or the environment.”

24 hrs after Suncor's tailing pipe burst, spilling toxic chemicals (several of which may be carcinogenic) for FOUR hours onto Alberta's landscape and waterways we still:1) Don't have pictures of the event;2) Don't know the chemicals that were released;3) Don't know how much was released;4) Don't know how the release was discovered; or5) How close the release was to the Athabasca river